Computer Science Ph.D. candidate · Georgia Tech

Phillip Si

Learning from uncertainty.
Modeling the physical world.

I work on probabilistic machine learning, generative data assimilation, and differentiable surrogate models. My research brings sparse observations and dynamical models together to build efficient, uncertainty-aware digital twins.

At Georgia Tech, I’m advised by Peng Chen and Chao Zhang. I also conduct research at Oak Ridge National Laboratory, following work at Argonne National Laboratory.

Two researchers collaborating at a whiteboard
At the whiteboardBased in Atlanta, Georgia

What I work on

Making sense of complex systems.

From a few measurements to a fuller picture of how the world evolves.

01

Generative data assimilation

Combining score-based generative models and Bayesian filtering to infer high-dimensional states from sparse, noisy observations.

Latent-EnSF · LD-EnSF · LD-EnFF
02

Differentiable dynamics

Learning compact surrogate models for efficient forecasting, joint state–parameter estimation, and model predictive control.

LEVDA · Neural ODEs · Flow control
03

AI digital twins

Bringing simulation, observations, and learning together for flood prediction, weather, and unsteady fluid dynamics.

CLDNet · C-STRIDE · Flood forecasting

Selected work

Recent publications

All publications

Along the way

Research experience

View my CV

May 2026 – Present

Oak Ridge National Laboratory

Graduate Researcher

Sparse-sensor estimation, latent forecasting, and control for unsteady fluid flow.

June 2025 – May 2026

Argonne National Laboratory

Research Aide

Rainfall-driven neural surrogates and digital twins for basin-wide flood prediction.

August 2023 – Present

Georgia Institute of Technology

Graduate Researcher

Generative data assimilation and differentiable latent models for physical systems.

Previously: machine learning graduate coursework at Carnegie Mellon, and a B.A. in Computer Science & Mathematics at Cornell, where I worked with Volodymyr Kuleshov.

Beyond research

Another kind
of experiment.

Away from research, I enjoy cooking and gaming. Here are a few things I’ve made in the kitchen.

Visit the kitchen
Homemade pistachio and herb-crusted lamb with sweet potato puréePistachio & herb-crusted lamb